Let people email you with the message already written
Scanning this code opens the reader's own mail app with a fresh message addressed to you, and — if you fill them in — the subject line and body already typed. They just add anything personal and hit send, which is why response rates on a feedback poster jump when there's nothing to compose from scratch.
It's built on the humble mailto link, the same thing a clickable email address triggers on a web page. Nothing is sent automatically; the code only drafts the message. The recipient stays in full control and can edit every field, including the subject and body you pre-wrote, before anything leaves their outbox.
What the sender actually sees
After the scan, their default mail client — Gmail, Apple Mail, Outlook, whatever is set — pops open a compose window. Your address sits in the To line, your subject in the subject line, your text in the body. They see and can change all of it.
That transparency is a feature: nobody is tricked into sending. But it also means the pre-written body should read as a helpful starting point ('Table 12 — my order was...'), not as words you're putting in their mouth.
Writing a subject and body that pull their weight
A good prefilled subject routes the mail for you: 'Booking enquiry — [poster location]' lands in the right folder and tells you where the scan happened. A short body scaffold lowers the effort to reply, which is the entire point of prefilling.
- Subject that identifies the source, so you know which poster worked.
- A one-line body prompt the sender completes, not a finished paragraph.
- Leave subject and body empty if you only want a blank message to your address.
How spaces and line breaks get encoded
Mail apps expect the subject and body to be percent-encoded — spaces become %20, line breaks become %0A, and symbols like & and ? get escaped so they don't break the link. This tool handles that for you.
If you ever build a mailto by hand and the body cuts off at the first space or an ampersand swallows the rest, missing percent-encoding is the culprit. Here you just type normally and the encoding happens underneath.
When no mail app is set up
The code assumes the phone has a working email account. On a device where mail was never configured, the scan may open an empty client asking to add an account, or do nothing visible. For a public-facing poster, printing the plain address alongside the code covers those users.
How to make an email QR code
- Enter the To address. This is the only required field. Double-check the spelling — a typo here sends every reply into the void and you'll never know people tried.
- Add a subject. Optional, but a specific subject like 'Feedback — Spring menu' tells you which code was scanned and files the mail sensibly.
- Write the body prompt. Optional. Type normally with spaces and line breaks; they're percent-encoded for you. Keep it a short scaffold, not a full message.
- Download and test send. Scan it, confirm the compose window opens with your fields filled, then send yourself a test before printing.
Technical details
- Maximum characters: 2953
- Recommended error correction: M (medium) — the mailto payload is short, so a balanced level keeps the code bold without wasting capacity.
- Payload format: mailto:<to>?subject=<subject>&body=<body>, with subject and body percent-encoded.
- Percent-encoding inflates length — every space becomes %20 — so a long body eats capacity faster than its visible character count suggests.
Frequently asked questions
- Does scanning the code send the email automatically?
- No. It only opens a draft in the reader's mail app with your address, subject and body filled in. They still have to press send. Nothing leaves their phone until they choose to, and they can edit every field first.
- What email app does it open?
- Whichever is set as the phone's default — Gmail, Apple Mail, Outlook, and so on. You can't force a specific one from the code; it hands the draft to the system, which routes it to the user's chosen client.
- Can the recipient change the subject and message I wrote?
- Yes. Everything you prefill is a starting draft, fully editable before sending. That's by design, so write the body as a helpful prompt they complete, not as a finished statement you want sent verbatim under their name.
- Why did my prefilled message get cut off?
- Almost always missing percent-encoding when a link was built by hand — a raw space, & or ? truncates the body. This generator encodes spaces as %20 and line breaks as %0A automatically, so typing normally here avoids the problem entirely.
- What if the phone has no email set up?
- The scan may open an empty client prompting the user to add an account, or appear to do nothing. It relies on a configured mail app. For a public poster, print your address in plain text next to the code as a fallback.
- How long can the subject and body be?
- The whole payload fits within 2,953 characters, and percent-encoding makes spaces and symbols take three characters each. A short subject and a one or two line body stay well inside that and keep the code easy to scan.